(1) Entry into and exit from a perfectly competitive industry will

1. Drive price to minimum Long-Run AVC
2. Produce economic losses for entering firms
3. Allow efficient managers to earn economic profits
4. Drive price to minimum Long-Run ATC

(2) Positive Economic Profits are

1. A long-run operating condition necessary for a monopolist
2. Profits above what it takes to keep the entrepreneur in that business
3. Equal to producer surplus
4. Equal to the markup of price over Average Total Cost

(3) Monopolistic competition is a market structure very much like perfect competition except that

1. The demand curves facing firms are perfectly price inelastic
2. Each firm has a strategy for how they will react to other firms' price or quantity
3. Entry and exit is not permitted
4. Firms differentiate the characteristics of their product